Our case study centers on two closely related models that are stochastic and biologically detailed: the off-lattice model [1]} developed by Volkening and Sandstede in 2018, and the on-lattice model [2]} built by Owen, Kelsh, and Yates in 2020. For the remainder of this manuscript, we refer to the former as the ABM [1]} and the latter as the CA [2]}; see Figure REF . In terms of the wild-type cell interactions that they describe and predict, the models [1]}, [2]} are largely the same from a biological perspective. They differ primarily in choices of computational implementation, which, in turn, affect how stochasticity shows up in cell behavior and pattern features. (We focus on the models [1]}, [2]} because of their biological similarities and mathematical differences; in the future, it would be interesting to consider other models that differ in the types of cells that they consider, such as [9]}, [10]}, [11]}, [12]}.) Both models [1]}, [2]} were built pre-publication of [15]}, in a biological environment in which the prevailing view was that iridophores may undergo shape and color changes. Because our focus is on developing methods for comparing similar models implemented in different ways, the new findings [15]} do not affect our study. We overview the ABM and CA here; see Appendix  for a deeper dive into a few example model rules, and [1]}, [2]} for full details.
